Why has Aristotle had such an astounding influence on the world? What are his key ideas? What can he still teach us today? The Lyceum in Athens, now a ruin, has a claim to be the most significant place in human history. It is the site of Aristotle's school. Here the philosopher taught and discussed the answers to the deepest mysteries of the human condition, and changed the way we think. Today, it can be difficult to fully comprehend the staggering influence of Aristotle's lessons. Yet his observations about the world around him and his reflections on the nature of knowledge laid the foundations for all empirical science. His study of rational thought formed the basis of formal logic, the cornerstone of philosophical investigation. His examination of Greek city-states gave us political science, while his analysis of drama remains a mainstay of literature courses around the world.